An electrode mixture is used for an electrode in a nonaqueous electrolyte secondary battery. As the nonaqueous electrolyte secondary battery, a lithium secondary battery is typical, and the lithium secondary battery has been previously put into practical use as an electric source of cell phones, laptop computers and the like, and further, there are trials of application thereof also in medium or large size applications such as an automobile application and an electric power storage application.
A lithium secondary battery usually comprises a positive electrode containing a positive electrode active material which can be doped or dedoped with a lithium ion and a negative electrode containing a negative electrode active material which can be doped or dedoped with a lithium ion, and an electrolyte.
An example of the electrode mixture includes a substance obtained by mixing and kneading an electrode active material such as a positive electrode active material and a negative electrode active material, a binder and a dispersion medium. As the binder and the dispersion medium, organic solvent based binders are typical, and examples of the organic solvent based binders include polyvinylidene fluoride (binder) and N-methyl-2-pyrrolidone (dispersion medium). On the other hand, it is known that water based binders are used as a binder and a dispersion medium in order to reduce high electrode production costs due to use of an organic solvent, and specifically an aqueous dispersion of polytetrafluoroethylene (JP2-158055A), water-soluble polymers such as cellulose and the like and water (JP2002-42817A) are known.